Improvement in artificial ston e



I Cross Reference JOSEPH A. GREER AND PETER IMPROVEMENT IN PATENT OFFICE.

OHAIR, OF STERLING, ILLINOIS.

ARTIFICIAL STON'E.

' Specification forming part of Letters Patent No. f 2l2,686, dated February 25, 1879; application filed December 27, 1878.

To all whom it may concern.-

Be it known that we, JosEPH A. GREER. and PETER OHAIR, of the city of Sterling, in the county of Whiteside and State of Illinois, have invented certain new and useful Improvements in the Mode of Making Artificial Stone; and we do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

Our invention relates to an improved compound for-artificial stone for building and ornamental purposes.

To use our invention, proceed as follows:

in s three pars; of Portland cement one 51??? 11 one par 0 '1 u ifiina, three parts. lese are thoroughly IDlXG-l an then moistened with the following solution: two

'per cent. of carbonate of magnesia, one per cent. of carbonate oi. SOt rum one per cent. of

litliarge, two per cent. oI sesg uioxide of iron an ninety-four per cent. 0 wa er. 1e compound is then ready for the molds. As such compound is tamped into the molds it is moistened during thepnocess of tamping with a solution of one-twentieth of the whole of the above of uni-shellac cut in the requisite amount of aIcoIIoI. Ill of the above proportions are ouu y weight.

When in the molds, the compound, moistened as above, is placed under pressure of Take of clean sand six parts; of stone-chipabout four hundred pounds to the square inch of upper surface, and allowed to remain there one day.

bonate of ma nesia one per cent. of carbonate of sodium, one per cent. of litharge, two per cent. of sesguioxide jrgp", and ninety-four per cent. of water,an with the further solution of one-twentieth of the above aggregate *for the purpose specified.

In testimony that we claim the foregoing as two witnesses.

JOSEPH A. GREER.

PETER OHAIRJ Witnesses:

J. J. OUsHINe, J. E. MCPHERRAN.

After the stone is taken from the molds it is again moistened from three to five of a alqe 1.2122 nese serremeneeefalcgjo subs antlally as here n described, and

our own we aflix our signatures in presence of 

